Self-starter for electric motors.



O.'H. MILLER.

- SELF STARTER FOR ELECTRIC E;QOTOR$.

APPLIOATIOH FILED OCT. 24, 190%,

62 Xxx/,

UNITED sTATEs PATENT OFFICE.

CHARLlu'd H. MILLER, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO THE CUTLER-HAMMER MANUFACTURING COMPANY, OITMILWAUKE E, WISCONSIN, A CORPORATION OF WIS-.

(VONSINI SELF-STARTER FOB ELECTRIC MOTORS.

Patented. May 11, 1909.

Application filed October 24, 1904 Serial No. 229,872.

drawing, forming a part of this specification.

My invention relates to improvements in self starters for electric motorsfand has for its object to provide means whereby the motormay be controlled by variations in pressure in a compression tank.

It is particularly adapted for use in coni nection with the self starters for electric motors, comprising broadly a rheostat for a motor having the movable element thereof operated through the medium of, a solenoid,-

and the present object of my invention is to provide means for automatically closing the circuit through said solenoid for operating said movable element when the pressure in a compression tank falls below a certain definite amount and for openingacircuit through said solenoid when the pressure in the compression tank rises to a predetermined point.

I have shown a diagrammatic view of my ention in the accompanying drawing orming a part of this specification.

In the preferred embodiment of my invention I provide a pressure regulator, 1, having contact points 2, and 3, formed thereon and a solenoid 4, which is adapted to operate the switch 5 and close the circuit between the two contacts 6 and 7. Magnetic blow-outs 5 are electrically connected to the contacts 6 and 7. The circuit controlled by this solenoid switch contains therein the solenoid winding 8, which operates the movable element 9 of the resistance 10, said resistance being subdivided into sections and connected with the series of contacts 11, over which said movable element 5 is adapted to sweep.

conductor 9" connects the hub of the coni; t arm ii with the second 01 the contacts 11, whereby in event contact between the arm an 5 the contacts should be defective, the armature current wi l still find a path through the conductor 9* and the resistance 10. The resistance 10 is connected in the circuit of the motor 12, having the field winding 13.

In operation, when the needle point 14 of the pressure regulator 1,,whicl1 is adapted to be moved over the lace thereof by the rise and fall of the pressure in a compression tank 1% is moved to the leit'by the lowering of the pressure it makes contact with'the contact point-2, and circuit is closed from the line 15, over the wire 16, to the binding solenoid winding 4, conductor 18 to the contact 2, of the-pressure regulator, over the needle point 14, by conductor 19, to the binding block 20, through the winding of the solenoid 4, by conductor 21, through the resupport for the self starter of the motor and from thence by conductor 26 over the movable element 9 by conductor 27, binding block 28, conductor 28 to the opposite side of the line 29. The resistance 42 will thereby be short circuited and sufiicient current operate its core and raise the contact 5, thereby closing the -circuit through the two contacts 6 and 7 and from thence to the motor. The motor circuit may be traced as follows: line 15, conductor 16, binding post 17, contact 6, movable contact 5, contact '7, conductors 30 and 30 armature 12, conductor 35, binding post 35", conductor 85, resistance 10, movable element 9, and back to the opposite side 29 of the line, the field circuit being traced from conductor 30,

binding block 37, conductor 38, binding block 28, and back to the opposite side 29 of the line. When the motor circuit is closed, circuit is also closed through the solenoid 8, which circuit may be traced as follows: conductor 30, binding post 30, winding of switch 32, conductor 33, conductor 27, binding block 28, and back to the opposite side 29 of the line. The winding of the solenoid 8 being thus energized, it operates the movable elem'ent 9, to move the same over the contacts 11,- thereby removing the resistance- 10 in the motor circuit, and causes the motor to gradually build up in speed. When the arm 9 has reached its final position. die switch is moved out of contact with the contact point 39 andthi-v resistance 40 is inserted in the circuit of the winding of the solenoid 8. After themovable element 9 has moved from the first contact 34, a re.- sistance 41 is inserted in the circuit 01' iii sistance 22, binding block 23, conductor 24, to the binding block 25, mounted upon the through field winding 13, conductor t6,

the solenoid 8, conductor 31, across the 4:

block 17, mounted upon the same base as the will be admitted to the solenoid winding 4 to winding of thesolenoid 4, thereby preventing the same from overheating.

As the motor operating the pump 12 gradually increases the pressure in the compression tank, the needle 14 moves to the right away from the contact 2 and them]:- rent through the winding 4 then asses through the resistance 42, to the win ing 4, instead of taking the shorterv path through the contact Zfand the needle of the pressure regulator. .Sufficient current howeverpasses through thesolenoid to maintainthe contact 5 in a closed position and the motor continues to run u/hti the pressure increases sufficiently to cause the needle to make-contact with the contact 3, which is connected by conductor 43, with the conductor 21,

thereby short-circuiting the same, so that the contact bridge 5 ,opens'the circuit between the contacts 6 and 7, thereby opening the motor circuitand stopping the same.

Under these conditions current may be traced from the binding ost 17;, through the resistance 42 to the con uctor 19 across the needle 14 to contact 3, and thence by condoctor 43, through the resistance 22,-to the binding post.23, from thence by conductor. 24 to the binding post 25, on the self starter, conductor 26, contact 34 of the motor resistance, through theresistance 41, hub of the movable element 9, conductor 2?, binding post 28, conductor 28Fand opposite side of the main 29. The resistance 22 is arranged in series with the contact 3 of the pressure switch to prevent arcing between the contacts 2 and 3 of the ressure switch when said contacts are set 0 ose together, as they usually are in pressure gages.

- 'Having described my invention What I claim as new and desire to secure byLetters Patent is:

1. The combination with a. motor, and a resistance therefor, of a magnetically operated switch controlling the circuit through said motor-and said resistance, means for re-.

' ducing the current traversing the magnet of said switch, ,a device responslve to flui pressure, which 1n one pos tion renders said means inoperative and in another position renders said magnet inoperative, and a resistance adapted to be included in circuit with said magnet, when the starting resistanoe, is removed from circuit, and adapted.

to be removed from circuit when the starting resistance is-in circuit.

2. The combinatlon with a motor anda resistance therefor, of a magnetically operated switch controlling the circuit through said motor and resistance, a resistance arranged in the circuit of the operating magnet for said switch, a shunt extending around said resistance, a fluid pressure operated switch arm moving between stops and adapted when in contact with one stop to close said shunt and when m engagement wlththe ditions rendering said magnet inoperative.

3. The combination with a motor,'of a controller therefor, an electromagnetic wmding'for automatically. actuating said controller, a magnetically operated switch for controlling the circuit through said motor and'said Winding, means for, reducing the current traversing the operating magnet of said switch," and a fluid pressure d'evice,

which is adapted inone position to render SLlClIllBfLIlS ineffective, and n another position to render said 'inagnetinoperative.

4. The combination witha motor, of a controller therefor, an electromagnetic winding for actuating said controller, a magneticcuit through said motor, and said winding,- a resistance arranged in thecircuit ofjthe con{ trolling magnet of s'aidswitch, a'shunt extending around said switch, and a fluid pressure operating switch arm, which is adapted when in one position'to, close'said shunt, and

in another positionto close a shunt circuit;

around saidmagnet, v I v ,A v

- ,5 The combination with a motor, of a controller therefor, an electromagnetic ninth ing for actuating said controller, a magnetically operated switch for controlling the circuit through saidf'motor andsaid'vnnding,

means for reducing the current traversing the operating magnet of said snitch, and

means for rendering said 1 reducing means ineffective under predeterminedconditions,

ally operated switch-for controlling the cirsaid means under other predetermined con-- 6. The combination with a motor, of a controller thereforfan' electromagnetic irinda ing for actuating saidcontroller,:a magnetically operated switch forl controlling the circuit through said motor and said winding, means for reducing the current traversing the operating 'inagnet of said switch, and a switch which inone position rendersfisairl' means ineiiective, and in another position renders said magnet inoperative.

'7. The combination with a motor, resistance therefor, a movable elementfor controlling said resistance, an olectromagnet for operatingsaid movableelement to re move said resistance from the motor circuit,

and an electromagnetic switchlor controlling the circuit throng said eloctromagnet, said electromagnetic switch lining operated to make said circuit by auto-name mcansclosing a shunt circuit around a resistance in series with said. electromagnetic switch and operated to brealrsaid circuit by autrnnatie means closinga shunt circuit"around said electromagnetic switch.

8. The combination with an-electromagnetic switch provided with a resistance in serieswiththe winding thereof, of automatic means for short circuiting said resistanceon the occurrence of redetermined conditions toxenergize said e ectromagnetic switch to close'a circuit through an electromagnet associated with a controller, and means connected with said controller for increasing a resistance in series with electromagnet. g

9. The combinatlon with a motor, o'l a controller therefor, an actuating electromagnet connected with said controller, an

-- electromagnetic switch for controlling the and controllercontinuity of the motor electromagnet clrcults, a resistance in series with said electromagnet c switch, and means for automatically short circuiting said resistoccurrenceof another kind of ance on theoccurrence of one k ind of predetermined conditions and for short circuiting the electromagnetic switch .on the predeter mined conditions.

10.,The combination with a motor, of a controller therefor, an actuating electromagnet connected with said controller, an

electromagnetic switch for controlling the continuity of the motor and controller eleccontinuity tromagnetic circuits, a resistance in series with said electromagnetic switch, means for automatically short circuiting said resistance on the occurrence of one kind-of predetermined conditions and for short circuitingthe electromagnetic switch on the occurrence of another kmd of predetermmed conditions,

and means connected with said controller for increasing the resistance of. the electromagnetic switch circuit.

. automatically short circuitingsaid resistance on the occurrence of one kind of predetermined conditions and for short circuiting the electromagnetic switch on the occurrence of another kind of predetermined condltlons, means connected withsai'd controller for increasing the resistance of the electromagnetic switch circuit, and means'associated with said controller for increasingthe reerated rheostat, of an electromagnetical operated motor switch, an automatically op:-

sistance of the controller electromagnetic circuit.-

12. In a controller for electric motors, the

combination with an electrom agnetically cp erated controlling switch circuit connections whereby sald controllmg switch, 1n one posi- -tio'n, causes the magnet of said motor switch to respond and close said motor switch and. r. causes the rheostat to operate to start the said controller:

motor and in another position causes the magnet of said motor'to be denergrzed, and

a maintaining circuit for energizing said magnet when said controlling switch is in an intermediate position. V

13. 'In a motor controller, the combination with an electromagnetically operated rheo'' stat, of an electromagnetically operated motor switch, a pressure operated switch, circuit connections whereby said pressure switch, in. one position, causes the magnet of said motor switch torespond to close said motor switch and causes the rheostat to operate to start the motor and in another position causes said magnet to be denergized, and a maintaining circuit for energizing said magnet when said pressure switch is in an intermediate position. r

.14. In a motor controller, the combination with an electromagnetically operated rheostat, of an electromagnetically operated motor switch, a pressure operated switch, circuit connections whereby said pressure switch, in one position, causes the magnet of said motor switch to respond and close said motor switch and causes the rheostat to operate to start the motor and in another position short-circuits said magnet, and a maintaining circuit for energizing said magnet when said pressure switch is in an intermediate position.

15. The combinationwith an electromagnetically operated switch, of anautomatically operated switch movable between stops,

said last mentioned switch'when in engagement with one of said stops being adapted to cause the energization of the operating winding of the first mentioned switch and when in engagement with the'other of said-stops to cause the de'nergization of said Winding, and a resistance connected in circuit with, one of said'st0ps to prevent arcing between said stops.

16. The combination with an electromagnetically operated switch, of an automatically operated switch movable between stops, said last mentioned switch, when in engagement with oneof said stops, being'adapted to cause the energization. of the operating winding of the first mentioned switch and when in engagement with the other of said stops to close a shunt-circuit, around said .winding', and a resistance connectedin circuit with said last mentioned stopand said winding to prevent arcing between said stops. p

17. The combination with an electromagnetically-operatedswitch, of a resistance con; nected in circuit with the oper'ati winding of said switch for rendering said winding in effective to close said switch, and 'a sure operated switch movable between stops, said pressure switch, 'when in engagement with one of said stops, being adapted to close a shunt-circuit around said reslstarice neticaiiy operatedsw'itchl of a; resistance con-1 scribed my nested in circuit with-the operating winding of saidswit ch forgr endsiing said winding ineifsctive foo'clos'e siaid switchyapr essure o'p'f l ;--W1tnesses:

eraped switch movablsbetweeii fixed stops,

said pressure switch, when in engagement with one of said stops," being adapted t close a; shuilt-circilit aroiind said resistance and when in engagement with the other of said stbps to 'close a; shtiiit-circiiitj around said winding, and &--I'.8Si$t8.1106 Connected in cir- 'uit With'Sa-id last mentioned stfop' and said- Windin'g to prevntami'ng betweeiisaidstops;

In witness wherebf, I have hereunto sub- :1 ILLER 5.; HENR H. CUTLER, I

J. F. HAWKINS.

20 pains in the prsence ofitwo wit 

